Treatment of bleeding wounds, particularly severely bleeding wounds, can require immediate attention to bring the bleeding under control. Severe bleeding poses a very real risk of death to the casualty if not treated quickly. Although loss of about 10-15% of total blood volume can be endured without clinical sequelae in a healthy person, if a laceration or penetrating trauma (e.g., knife or gun wound) is severe enough or involves critical arteries or veins, this volume of blood can be lost in a matter of minutes. The bleeding must be slowed immediately or irreversible damage to organs and mortality can result.
Bleeding wounds, even those that may be less severe, can pose serious difficulties and risks when a severe wound is inflicted in a remote area or other≧situations (such as found in a battlefield) where full medical assistance may be not immediately available. In such circumstances it can be critical to undertake measures to slow or stop bleeding so that the subject can be transported to a medical facility.
Various methods and hemostatic compositions for promoting blood clotting have been developed, and can be applied to help control bleeding in such situations. Exemplary compositions include those composed of bound zeolite (see, e.g., U.S. Pat. No. 4,822,349). Such zeolite/binder compositions, such as QuikClot®, can have a water content of about 1.54% or less as estimated by measuring the mass of material before and after heating at 550° C. (i.e., Loss on Ignition (LOI) at 550° C.). Higher temperatures are sometimes used for LOI calculations, but procedures that utilize these higher temperatures increase the loss of chemical compounds other than water. Further exemplary hemostatic compositions include those that composed of partially hydrated zeolite, such as described in US 2005/0059721.
The field continues to develop additional hemostatic compositions that provide for, for example, rapid initiation of blood clotting, increased rate of blood clotting, sufficient blood clot strength, and/or reduced adverse side effects (e.g., due to heat that can be generated locally as a result of enthalpy of hydration that may be associated with use of certain hemostatic agents, such as dry bound zeolite), and which can optionally deliver antibiotics and/or wound healing-promoting agents, and/or pro-thrombotic agents, and/or ions. Of particular interest are such hemostatic compositions that can be rapidly and safely applied in an emergency situation, such as on the battlefield or at the scene of an accident, without the need for intensive training or equipment.
Literature
U.S. Pat. Nos. 4,748,978; 4,822,349; U.S. Pat. No. 4,373,519; US 2003/0133990; US 2005/0074505; US 2005/0058721; US 2006/0141060; US 2007/0004995; US 2006/0211971; US 2006/0211965; US 2006/007862; US 2006/0155235; WO 06/088912.
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